1. Field of the Invention
The present invention relates generally to the field of wind turbines and more particularly to a wind turbine having a plurality of wind-catching sails attached to a pair of parallel chains each configured as a dosed loop for driving sprockets which, in turn, rotate a shaft of an electrical generator.
2. Background Art
Conventional wind turbines employ propeller blades rotating about a horizontal axis to turn a shaft of an electrical generator. Unfortunately wind turbines of such conventional configuration have limited efficiencies due to the high propeller tip speeds. In addition, the propeller angle of attack varies with distance to the center. The sweet spot of efficiency is limited and small. Therefore, there is a need for a wind turbine which is configured to be more efficient over a broader range of wind speeds. In observing wind surfers using a triangular sail to speed along at speeds of about 40 MPH, Applicant conceived an improvement in wind turbines wherein sails of rectangular shape (to double the developed thrust compared to wind surfers) are secured to chains which are more efficient than gears used in propeller wind turbine designs. A sail on a chain is more efficient than an elongated propeller blade because a rectangular sail promotes full power development evenly across the entire sail surface. Therefore, Applicant believes that the uniquely-configured wind turbine employing sails on a chain as disclosed herein for example, can render obsolete more conventional propeller-based wind turbines and help make America less dependent on the need for importing foreign oil.